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91.
Bacteremia due to a novel Microbacterium species in a patient with leukemia and description of Microbacterium paraoxydans sp. nov 下载免费PDF全文
Laffineur K Avesani V Cornu G Charlier J Janssens M Wauters G Delmée M 《Journal of clinical microbiology》2003,41(5):2242-2246
A yellow-pigmented coryneform rod was isolated from the blood of a child with acute lymphoblastic leukemia who was perfused with a central venous catheter. The culture bottles were positive twice, at a 2-month interval. The isolate was identified as a Microbacterium sp. and studied along with five other similar strains. Phenotypic, chemotaxonomic, and genetic characteristics indicated that they are closely related to Microbacterium oxydans but that they belong to a distinct species, for which the name Microbacterium paraoxydans sp. nov. is proposed. The type strain of M. paraoxydans is CF36(T) = DSM 15019(T). The G+C content of its DNA is 69.9 mol%. 相似文献
92.
Thierry Janssen MD Michel Petein MD Roland van Velthoven MD Patrick van Leer MD Marc Fourmarier MD Juan-Pablo Vanegas MD Andre Danguy PhD Claude Schulman MD Jean-Lambert Pasteels MD Robert Kiss PhD 《Human pathology》1996,27(12):1341-1347
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors. 相似文献
93.
Immune monitoring in whole blood using real-time PCR 总被引:7,自引:0,他引:7
Stordeur P Zhou L Byl B Brohet F Burny W de Groote D van der Poll T Goldman M 《Journal of immunological methods》2003,276(1-2):69-77
94.
Staelens S Strul D Santin G Vandenberghe S Koole M D'Asseler Y Lemahieu I Van de Walle R 《Physics in medicine and biology》2003,48(18):3021-3042
Geant4 application for tomographic emission (GATE) is a recently developed simulation platform based on Geant4, specifically designed for PET and SPECT studies. In this paper we present validation results of GATE based on the comparison of simulations against experimental data, acquired with a standard SPECT camera. The most important components of the scintillation camera were modelled. The photoelectric effect. Compton and Rayleigh scatter are included in the gamma transport process. Special attention was paid to the processes involved in the collimator: scatter, penetration and lead fluorescence. A LEHR and a MEGP collimator were modelled as closely as possible to their shape and dimensions. In the validation study, we compared the simulated and measured energy spectra of different isotopes: 99mTc, 22Na, 57Co and 67Ga. The sensitivity was evaluated by using sources at varying distances from the detector surface. Scatter component analysis was performed in different energy windows at different distances from the detector and for different attenuation geometries. Spatial resolution was evaluated using a 99mTc source at various distances. Overall results showed very good agreement between the acquisitions and the simulations. The clinical usefulness of GATE depends on its ability to use voxelized datasets. Therefore, a clinical extension was written so that digital patient data can be read in by the simulator as a source distribution or as an attenuating geometry. Following this validation we modelled two additional camera designs: the Beacon transmission device for attenuation correction and the Solstice scanner prototype with a rotating collimator. For the first setup a scatter analysis was performed and for the latter design. the simulated sensitivity results were compared against theoretical predictions. Both case studies demonstrated the flexibility and accuracy of GATE and exemplified its potential benefits in protocol optimization and in system design. 相似文献
95.
Albert Beckers Kalman Kovacs Eva Horvath Roger Abs Michel Reznik Achille Stevenaert 《Endocrine pathology》1991,2(3):123-131
Twenty-four acromegalic patients were treated with octreotide subcutaneously for periods of 3 to 6 weeks (group I, 12 cases)
or 6 months (group II, 12 cases) before transsphenoidal surgery. Radiological studies performed in 19 patients before and
at the end of this treatment period revealed no changes in 8 cases. In 8 other cases, a slight reduction in tumorsize was observed, and in 3 cases an important shrinkage was documented. At surgery, the adenomatous tissue appeared softer than
in nonpretreated patients, facilitating the operation. Pathological examination revealed widening of perivascular spaces with
accumulation of fibrous tissue and more crinophagy than in nonpretreated patients but failed to reveal morphologically pronounced
cell involution as observed in prolactin-producing adenomas treated with dopamine agonists. No significant difference in frequency
or extent of cellular changes was noted between the two groups. These morphological findings seem to be more consistent with
a functional inhibition of growth hormone release than with cellular alterations induced by octreotide. 相似文献
96.
Bruno Amduri Khalid Berrada Bernard Boutevin Michel Mlas Roy D. Bowden 《Macromolecular chemistry and physics.》1993,194(11):3001-3014
The synthesis of novel telechelic monodispersed diols produced from the radical monoaddition of an excess of 10-undecenol with novel α, ω-dithiols, initiated by peroxides, is presented. The telechelic dithiols employed were prepared from nonconjugated dienes and a commercially available dithiol, or by esterification of adipic acid with 2-mercaptoethanol. From these dithiols, the diols were selectively obtained in high yields. Such α, ω-dihydroxylated compounds were characterized by both 1H and 13C NMR spectroscopy. The diol which exhibits the ester functions shows excellent solubility in common organic solvents contrarily to the other ones. The physical properties (Tg, Tm and decomposition temperatures) of these diols were compared and it is noted that the thermostability of these monodispersed telechelic diols is much better than those of the polydispersed commercially available ones such as poly(ethylene glycol)s or poly(tetramethylene glycol)s. 相似文献
97.
98.
99.
Adjunct effect of loratadine in the treatment of acute sinusitis in patients with allergic rhinitis 总被引:1,自引:2,他引:1
J. J. Braun J. P. Alabert F. B. Michel M. Quiniou C. Rat J. Cougnard W. Czarlewski J. Bousquet 《Allergy》1997,52(6):650-655
H1 -blockers are often added to the standard treatment of acute sinusitis, but this is not supported by a controlled study. A multicentric, randomized, double-blind, placebo-controlled, parallel-group study was done in 139 allergic patients (15–65 years) to assess the adjunct efficacy of loratadine in acute exacerbation of rhinosinusitis. Sinusitis was diagnosed by symptoms and confirmed by rhinoscopy and sinus radiograph. Allergy was characterized by skin tests, RAST, and history. Patients were treated with antibiotics (14 days), oral corticosteroids (10 days), and loratadine (10 mg OD) or placebo (28 days). Treatment efficacy was assessed over 28 days by symptom scores quoted daily by patients. Physicians also rated total symptom scores at entry and at day 28. At entry, both groups had similar symptoms. Placebo-treated patients improved significantly, but patients who received loratadine had a significantly greater improvement in sneezing ( P =0.003) after 14 days, and in nasal obstruction ( P =0.002) after 28 days. Physicians found that patients receiving loratadine were significantly improved compared to placebo patients ( P =0. 0125). Loratadine in addition to standard therapy was found to improve the control of some symptoms of sinusitis. 相似文献
100.
Bernard Arnoux Jaqueline Durand Michel Rigaud B. Boris Vargaftig Jacques Benveniste 《Inflammation research》1981,11(6-7):555-556
Human, monkey and rat alveolar macrophages (AM) release PAF-acether in a dose-dependent fashion in the presence of 1 to 5 g/ml ionophore A 23187 (2.5 pmol of PAF-acether from 2.5×105 cells) but not in the presence of zymosan. Arachidonic acid (AA) metabolites released from AM from these species were studied. Thromboxane A2 TxA2)—detected by its action on rabbit arteries—was released from human, monkey and rat AM upon addition of 0.5 mM AA. This release was inhibited by aspirin and indomethacin. Lipoxygenase and cyclooxygenase AA metabolites from rat AM were identified using high efficiency glass capillary column gas chromatography coupled to mass spectrometry. The cyclooxygenase metabolites PGF2, E2 and D2 and TxB2 were identified. The lipoxygenase-dependent AA metabolites were explored using aspirin-pretreated AM. Only 12 HETE was found.These data indicate that AM secrete several substances with bronchoconstrictive activity: PGF2, D2, TxA2 and PAF-acether. Therefore an active role of AM in human and experimental bronchoconstriction must be considered. 相似文献